api: add tag pager to /media/:media_id

lib/PoorBooru/API/V0/Controller/Media.pm

@@ -70,6 +70,7 @@ sub show ($self)
 		download     => $media->seaweedfs_fid,
 		content_type => $media->content_type,
 		tags         => [ @tags ],
+		pager        => { $self->pager($paged_media_tags->pager) },
 	});
 };